Sign Up for a Free Account

This is an image preview.
Start a Free Account
to view the full image.

  • Nearly 3,000 illustrations, including video clips of neurologic disorders.

  • Every article is reviewed by our esteemed Editorial Board for accuracy and currency.

  • Full spectrum of neurology in 1,200 comprehensive articles.

  • Listen to MedLink on the go with Audio versions of each article.

Schematic location and functioning of the RFC in hepatocytes, small intestine, colon, and epithelial cells of the choroid plexus

Folates from supplementation (eg, folic acid and 5-methyl-THF) are transported intracellularly from the lumen of the proximal small intestine by the reduced folate carrier (RFC; folate transporter 1; SLC19A1 [Solute Carrier Family 19 Member 1]). RFC is also designated as solute carrier family 19 member 1 (SLC19A1). RFC is the main pathway for folate delivery from the serum and extracellular space. In the diagram, an apical surface of polarized epithelial cells is marked by irregular contour.

Abbreviations: 5-methyl-THF = 5-methyl-tetrahydrofolate. (Source: Shulpekova Y, Nechaev V, Kardasheva S, et al. The concept of folic acid in health and disease. Molecules 2021;26(12):3731.) (Modified by Dr. Douglas Lanska. Creative Commons Attribution 4.0 [CC BY] license.)